SAS notes 1

8/6/2019 SAS notes 1

1/42

1.Overiew of SASBase/SAS is the core foundation fora variety of data management and

analytical software componentsoffered by SAS.


2/42

1.Overiew of SASBase/SAS provides the essential tools for the

basic data driven tasks that are commonly

performed by a programmer. Data access

Management

Analysis Presentation.


3/42

1.Overiew of SAS


4/42

1.Overiew of SASSAS programming language is used to

Access data from many sources

Manage your dataAnalyse the data and present it as

meaningful information in a report that canbe delivered to any platform , in any formatneeded.

Data access management analysisand presentation


5/42

1.Overiew of SASAccessing data:

SAS can access data

That is stored almost anywhere whether itis in a file on the system , or the data that isstored on a remote server or in anotherdatabase system.

That is almost in any format including theraw data sets, SAS data sets and filescreated by other software.


6/42

1.Overiew of SASTypes of files that can be accessed:

Relational databases: DB2, oracle, teradata,

MS SQL server.

Non-relational database: ADABAS, PC file

formats, System 2000 software.

Enterprise resource planning (ERP) systems:Baan, SAP BW.


7/42

1.Overiew of SASManaging data:

SAS programming language is used to

manipulate the data .We can use it forformatting the data , creating the variables ,use operators and functions to evaluate,create and recode data values, subset the

data ,perform conditional processing mergedata sources, create , retrieve and updatedatabase information.


8/42

1.Overiew of SASAnalyzing data and presenting

information:

Once the data is proper ,SAS is used toanalyze data and produce reports. SAS

output can range from a simple listing of a

dataset to customized reports of complexrelationships.


9/42

1.Overiew of SASSAS is a powerful data analysis tool. We can

produce tables , frequency counts and

cross tabulation tables, create a variety ofcharts and plots, compute a variety of

descriptive statistics , including mean , sum

, variance etc, compute correlations and

other measures of association, as well as

multi-way cross tabulations and inferential

statistics.


10/42

1.Overiew of SASPresentation:

SAS has limitless number of visually appealing output formats ,such as,

An array of markup languages including HTML4 and XML. Output that is formatted for a high resolution printer , such as

post script , PDF, and PCL files

RTF

Color graphs tht can be made interactive using Active X

controls or Java applets.these can be later sent to a variety of locations and platfoms.


11/42

2.Explore SAS workspaceWhen SAS is started ,five main windows

open.

The explorer window

The results window

The log window

The editor window

The output window.


12/42

2.Explore SAS workspaceTHE EXPLORER WINDOW:

This is to view and manage the SAS files and

create shortcuts to files that are notformatted by SAS. This window is used to

Create new SAS libraries and SAS files.

Open any SAS file.

Perform most file management tasks suchas moving, copying, and deleting files.

Create shortcuts.


13/42

2.Explore SAS workspaceTHE EDITOR WINDOW:

This window is used to enter, edit, and submit SASprograms. This provides useful editor features like

Color coding and syntax checking of SASlanguage

Expandable and collapsible sections

Recordable macros

Support for keyboard shortcuts

Multilevel undo and redo.


14/42

2.Explore SAS workspaceTHE LOG WINDOW:

This displays the messages about the SAS

session and any SAS programs that aresubmitted.


15/42

2.Explore SAS workspaceTHE OUTPUT WINDOW:

This displays the output from SAS programs

that are submitted.NOTE: Not all SAS programs create output in

the output window. Some programs open

interactive windows. Others producemessages in the log, and few others

produce in the results viewer window.


16/42

2.Explore SAS workspaceTHE RESULTS VIEWER WINDOW:

This helps to navigate and manage the

output from SAS programs that aresubmitted.


17/42

2.Explore SAS workspaceAlong with all these SAs provides a set of

ready-to-use solutions , applications and

tools. These are available in the toolsmenu.

SAS also has online helpwhich is available

from the help menu.


18/42

3.Work with SAS data setsBefore any work is done , the data has to be in a

special form called a SAS data set.

SAS data set (or a table) is a file containingdescriptor information and related data values.

This is organized as a table of rows

(observations) and columns (variables) that can

SAS process. Some SAS datasets also containan index, which enables SAS to locate records in

the data set.


19/42

3.Work with SAS data setsAll SAS files are stored in a SAS library. This

is a collection of files such as SAS datasets

and catalogs.To access a library , a name is assigned

(libref). These are the shortcuts that are

used to identify libraries during a SAS

session.


20/42

3.Work with SAS data setsView SAS files in a library:

Go to explorer window

Double click libraries(see three imp libraries-sashelp, sasuser, work)

Double click sashelp library

Scroll down to see several types of files in the library (sas dataset/view/catalog/MDDB)


21/42

3.Work with SAS data sets

Assign a library:

When a library is defined , location of the

SAS files to SAS is indicated. Once thelibrary is defined d, SAS files can be

managed within it.


22/42


On the toolbar , click new library icon

Type the name of the library

Select enable at start up

Click browse and select the location. Click ok

Assign a library


23/42


Add and rename SAS data set

With explorer window active select view | show tree. (librariesare displayed)

Click SAShelp library

Drag the data set from the right pane and drop it into the desiredlibrary

Click the library to find the data set in the library. Right click andselect rename and type the new name.


24/42


There are many ways to get data into SAS data set.

Enter data directly into SAS using view table window

Read raw data into SAS using import wizard or proc

statements Read and modify existing data sets using SAS programming

statements

Convert other software data files into SAS data set bySAS/Access

Read other software data directly using SAS/Access


25/42


Open a SAS data set:

Select the library from the explorer window

Select the data set that is to be viewed and

worked on

Scroll the view table and notice study the

data values.


26/42


Descriptor portion of SAS:

The descriptor portion of SAS data set

contains information about the data set.This includes

Name of the data set

Date and time of the creation of the data

set Number of observations

Number of variables


27/42


View properties of data set

Right click on the data set and select

properties

Click on the column tab to view the details ofthe variables

The format of the column can be changedusing format option.


28/42

4.Create and run SAS programs

The SAS language contains

statements,expressions, functionsand

CALL routines , options, formats andinformats elements that many

programming languages share.


29/42


SAS also simplifies programming with its library ofbuilt in programs known as SAS procedures. SASprocedures uses data values from SAS data sets

to produce preprogrammed reports, requiringminimal effort. BASE/SAS procedures enables to

Manipulate data

Store and retrieve information

Perform statistical analysis Create reports.


30/42


Components of SAS programs:

SAS basically has two steps the DATA step

and the PROC step. These two types ofsteps, alone or combined, form all SAS

programs.


31/42


DATA steps typically create or modify SAS data

sets. They can also be used to produce custom

designed reports. Data steps are generally used

to

Put the data into SAS data set

Compute the values for new variables

Check for and correct errors in the data set. Produce new data sets by subsetting, merging

and updating existing datasets.


32/42


PROC (procedure) steps typically analyze and process data inthe form of a SAS data set,and they sometimes create SASdata set that contain the results of the procedure. PROCsteps control a library of prewritten routines that perform

tasks on SAS datasets, such as listing, sorting andsummarizing the data.

PROC steps are generally used to

Print a report

Produce descriptive statistics

Create a tabular report

Produce plots and charts


33/42


Characterization of SAS programs:

SAS programs are made up of SAS statements. ASAS statement has two important characteristics-

It begins with a keyword.

It ends with a semicolon.

A data step begins with the keyword DATA and theproc step begins with keyword PROC. Ends witha RUN statement which tells SAS to process allthe preceding lines of the step.


34/42


SAS statements are free format.

They can begin and end anywhere on a

line. One statement can continue over several

lines

Several statements can be run on a line.

SAS statements are not case sensitive.Blanks or special characters separate thewords in a SAS statement.


35/42


Copy a SAS program into the editor window:

Define the library

Create the dataset

Copy a sample SAS program in the editorwindow (notice SAS keywords are colorcoded and the program steps separatedinto expandable blocks.


36/42


Submit the program and view the output:

When a program is submitted ,SAS compiles and executes thecode and returns any results to the output window.

With the editor window active select run|submit.

View the log:

Each time a step is executed , SAS generates a log ofprocessing activities and the results of the processing. The

SAS log collects messages about the processing of SASprograms and any errors that may occur.

Click the log window to activate the log.


37/42


Use the results window:

Once the output is created , the results

window opens. The results node at the topof the window contains a folder for the

output of the procedure. The folder is

labeled with the procedure name and the

title of the report.


38/42


Create HTML output:

Select tools > options > preferences.

Click the results tab.

Select the create HTML check box.

Click ok.


39/42


Modify the program:

We can add options to the programs to

Remove the date from the top of eachpage.

Replace the default the SAS system title.

Use the column label rather than thecolumn name in the output.

Remove the obs column.


40/42


To remove date from the top of each page useNODATE system option and paste it at the top ofthe program.

options nodate; To replace the default title , use TITLE statement.

title life is beautiful;

To remove obs column and use column labels,use options on PROC PRINT statement.

Proc print data=xyz label noobs;


41/42


View and Save results:

HTML results can be created and saved in HTML files.

In the results window, scroll the HTML results.

With results viewer window active, select file > save as. In thefilename box, type the name and click save.

The results window now shows a new folder for the results of

the program .double click on the folder to view the output.


42/42

4.Create and run SAS programsSave a SAS program and set up a favorite folder:When SAS programs are saved , we can store them in a folder that is easy toaccess from the explorer window.

With the editor window active, select file > save as.

This opens to default folder on the system . In filename box , type the name

and click save. The file is saved with a .sas extension, indicating that it is aSAS program.

In explorer window, double click favorite folders

Right click in the favorite folders window and select new favorite folder.

In the new favorite folder window type , type folder name in the name box.

Click browse. The select window opens to the same default location where theprogram was saved. Click ok.

SAS notes 1

Documents

Transcript of SAS notes 1